RANTES is a chemokine expressed 3-5 days after T cell activation. Our analysis of the RANTES promoter revealed that the transcription factor KLF13 is the major activator of RANTES expression in T cells, while rel proteins are the major inducers of the immediate increase in RANTES observed in other cell types such as fibroblasts and monocytes. Kinetic analysis of the RANTES promoter for 7 days after T cell activation showed that a variety of transcription factors move on and off the promoter over time and that phosphorylation, acetylation, and deacetylation are all important for RANTES transcription. To study more closely the role of KLF13 in vivo, mice in which the KLF13 gene was disrupted were generated. Using DNA microarrays comparing wild type and KLF13 knockout animals, we found that KLF13 is involved in the transcriptional regulation of many genes. For example KLF13 is a negative regulator of BCLXL, a potent regulator of apoptosis. In August 2007, my group relocated from Stanford University to the NCI. Thus, during early 2008 we equipped the laboratory and hired key personnel. We began experiments in October 2007 and are actively pursuing studies in the following areas: 1. Identify genes regulated by KLF13. The hypothesis is that a "cassette" of co-regulated gens work together in disease. The KLF13 knockout mice are used to identify genes regulated by KLF13 (microarray analyses) and to evaluate the role of KLF13 in animal models of human disease. In parallel, chromatin immunoprecipitation assays and ChIP-Seq, which combines chromatin immunoprecipitation with ultra high-throughput massively parallel sequencing, is being used to identify genes regulated by KLF13 in human T cells. 2. Manipulate expression of genes regulated by KLF13. Members of the complex are being identified by tandem affinity purification (constructs are being made). The role of the ubiquitin pathway in KLF13 degradation is being evaluated. Small molecule screens for induction or interruption of KLF13 binding to its DNA binding site and/or regulation of gene expression is being tested in fluorescence polarization and cell based assays. Constructs for these assays are under development. These studies are aimed at designing new therapeutics for human diseases as diverse as cancer, tuberculosis, malaria, AIDS, and autoimmune diseases including diabetes, rheumatoid arthritis, and mutliple sclerosis.